MEXICO CITY — The Mexican government said Monday it has filed a form of affidavit expressing its concern over Texas’ “sanctuary cities” law, which is supported by the Trump administration.

Mexico’s affidavit is meant to help legal efforts by some police chiefs and immigrant-rights groups in Texas to stop the law from taking effect in September.

A federal judge in San Antonio is reviewing the constitutionality of the law, which allows police officers to question people about their immigration status during routine stops.

It also threatens police chiefs and elected officials with jail time and removal from office if they don’t comply with federal immigration requests to detain immigrants in the country illegally.

Carlos Sada Solana, Mexico’s assistant secretary of foreign relations, said Monday the affidavit will express Mexico’s concerns that the law “further criminalizes the phenomenon of migration.”

The affidavit includes data on a big jump in the number of calls to an immigration advice hotline and requests for legal assistance at Mexican consulates since May, when Republican Gov. Greg Abbott signed the bill, known as SB4.

Sada Solana said “in our community there is concern, there is discomfort, and there is fear of this situation.”